Time to make the 401k mandatory?

There are a slew of 401k reform plans out there, ranging from modest proposals for automatic employee enrollment (but undercut by the employee's right to opt out) to replacement of the 401k by a new system run by the government or a nonprofit organization. (For a useful description of the various ideas, see a study by Robert Hiltonsmith for Demos, a liberal think tank that espouses total overhaul.)